/*
package NiuKe;

import java.util.Scanner;

*/
/**
 * @Description:
 * @Author: Hanzao
 * @Date: 2022/06/14/20:11
 *//*

public class HJ53 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int num = scanner.nextInt();
        if(num == 1||num==2){
            System.out.println("-1");
        }else{
            if((num-2)%4==0){
                System.out.println(4);
            }
            else if(num%2==1){
                System.out.println(2);
            }else {
                System.out.println(3);
            }
        }
    }
}
*/
